摘要:

A prototype scanning laser microscope has been developed for remote examination of radioactive samples. The system produces both a conventional reflective image in bright field and a polarized light image in a form suitable for interface with a computer, of near-diffraction-limited performance.

DOI:10.1049/jiere.1985.0050

出版商:IERE    

年代:1985

数据来源: IET

摘要:

Methods of measuring electrical bonding of large, complex structures such as aircraft are discussed. The importance of measurement method design and result interpretation are stressed. The methods which are described are either large scale, such as potential plotting, potential mapping and infra-red scanning, or examine a small area, such as the resistance of individual fasteners. These methods have all been usedin situon service aircraft or large mock-ups. The limitations on the measurement methods are pointed out and the potential uses of the results, to predict poor bonding areas, set specifications etc., suggested.

DOI:10.1049/jiere.1985.0051

出版商:IERE    

年代:1985

数据来源: IET

摘要:

Experience, particularly in the US military field, has highlighted the problems of escalating software support costs in computer-based systems. This has resulted in the realization that software should be developed with the aim of minimizing through-life support costs rather than initial procurement costs, thus allowing software to be supported over periods of up to 20 years and be transported over successive generations of hardware without the major cost of replacement of the software.Although the problems of designing and implementing software which is capable of a long life span are becoming better understood, the problems associated with the management of software to achieve this life span are less well understood.This paper discusses topics such as quality plans, documentation standards and configuration management and describes the methods which may be applied to the management of software to enable the benefits of the initial investment to be realized.

DOI:10.1049/jiere.1985.0052

出版商:IERE    

年代:1985

数据来源: IET

摘要:

A brief outline is given of oscillator noise theory in order to introduce the concept of a noise measure as a means of defining a figure of merit for oscillator devices. Details are then given of a.m. and f.m. noise measurement techniques as applied to devices operating at millimetre wave frequencies. Using these techniques a comparison is made of the relative noise performance of both GaAs and InP transferred electron devices (t.e.d.s) and Si double-drift Impatt devices. It is thus shown that GaAs and InP t.e.d.s exhibit very similar noise performances with InP having the advantage of a higher power and efficiency capability. More surprisingly the results also prove that the Si double-drift impatt can exhibit low-noise behaviour under certain bias conditions. Finally it is concluded that the choice of oscillator devices for millimetre wave uses is more complex than previously thought and the double-drift impatt is now a real contender for low-noise systems use.

DOI:10.1049/jiere.1985.0053

出版商:IERE    

年代:1985

数据来源: IET

摘要:

The factors influencing the design of video tape recorders are examined and the relative advantages and disadvantages of analogue and digital approaches are evaluated. It is concluded that further developments are necessary before digital techniques can be realized economically and analogue methods still have a serious role in the development of future studio centres.

DOI:10.1049/jiere.1985.0054

出版商:IERE    

年代:1985

数据来源: IET

摘要:

The paper explores the problems posed by the introduction of component-coded components of vision signals from the point of view of the studio recorder. These involve f.m. noise, and the choice of format. The results of experiments are discussed and the lines of future work indicated.

DOI:10.1049/jiere.1985.0055

出版商:IERE    

年代:1985

数据来源: IET